LIFE OF and Humboldt at once remembered the volcanos mentioned in Chinese books as lying far from the ocean, and which had excited much surprise among geologists in Klaproth/s and Amusat's literary de- scriptions. Humboldt subsequently obtained more acctirate information from the Russian police-director of Semipalatinsk, von Klostermarm. He devoted special attention to this subject, and on his return composed a highly interesting sketch of the geo- graphy of this little-known district, with the object of bringing the remarkable volcano into organic re- lation with the other phenomena and conditions of the district. The famed rock-salt mines of Jlc!zk, in the steppe of the minor tribe of Kirghicles, and the chief station of the Uralskian Cossacks, was the next point on his journey. Then he arrived at the German colonies on the Wolga, in the department of Saratow, at the large salt-lake Elton ; and then visited the fine colony of Moravian brethren in Sarepta, and arrived in Astrachan, on the Caspian Sea, in the middle of October. His chief objects in this expedition to the Caspian Sea were to analyze the waters of the largest inlaiad sea of the world with chemical accuracy, and to dis- cover its constituent elementsa task which Gustav Hose undertook; then to make barometric measure- ments comparative to tBe measurements in Orenburg, Sarepta, and Kasan, and to collect zoological trea- sures. The specimens of fish from the Caspian Sea were to complete the work on fishes by Cuvier and Valenciennes,* and Humboldt arranged a little excur- sion by steamer on this*lake, for the purpose of collecting them. From Astrachan they returned to Moscow, over the isthmus which separates the rivers Don and Wolga, near Tischinskaya, through the territory of the Don ^ * Of the fish here caught., Humboldt sent a very complete collec- tion to the Museum of Natural History, in the Botanical Gardens of Paris.